While deer do eat grass from time to time, it is not their preferred meal. Deer prefer to browse on broad-leaf and flowering plants. Not all grass species are equally nutritional enough to make up a significant part of a deer’s diet.
We have done some extensive research on deer grass-feeding habits including video proof, research papers, and reasons why will deer choose grass and when they’ll not.
Let’s dig it all up!
Do deer like to eat grass?
In short, not really! Deer enjoy eating the new growth of woody plants as well as the leaves and flowers of forbs. Deer also enjoy fruits (bananas), vegetables (carrots, cabbage, pumpkins), roots, and other forages (peanuts, soybeans,).
Grass has no significant nutritional value other than cereal grasses, so deer will not seek it out unless on the brink of starvation. Grass makes up less than ten percent of a deer’s diet.
Despite its invaluable nutrients, the grass is not typically harmful to deer. It’s just not beneficial! Some cultivated grasses, such as oats and wheat, are more popular choices than lawn grass.
Because grass isn’t an important part of a deer’s diet, it’s considered a pretty deer-resistant plant. Decorative grasses, once mature, are rarely touched by deer. Young, tender shoots might be nibbled on, however.
Deer will sometimes dig up lawns in search of roots or grubs to eat. This is often mistaken for eating the grass, which is not the case.
Take this case, put grass and carrots next to each other, without even asking you; deer will munch on carrots because deer fall into Concentrate Selector (CS) that chooses easily digestible & highly nutritious plants over the inverse. But how? Studies have shown that Deer has highly motile, narrow muzzle and Prehensile lips that allow them to select highly nutritious meals.
Also, their small body size doesn’t need a copious amount of nutrients for maintenance, freeing them to spend more time finding better quality forages.
When is the best time of year to feed grass to deer?
The grass is not suitable food for deer. They will not eat it unless they are starving. Even then, a deer can starve with a stomach full of grass- their digestive systems are not designed to break it down. The cellulose in grass prevents a deer’s small rumen (a digestive stomach) from adequately extracting nutrients.
The only grasses that deer can digest easily in their rumen are small grains, ryegrass, and some native species.
Spring is the most likely time for deer to consume grass, as the young shoots are still tender and more easily digestible. It is still an unlikely choice, though, as there are many other more nutritious and tasty options beginning to appear in spring.
Evidence of deer eating grass
This tract will walk you through all shreds of evidence that clearly show deer eat grass.
A study done on deer, from the road kills including its food choices from all three seasons. It was found that the diet contained over 60% grass during the summer, though, deer ingested fruits & nuts, fern, bramble, conifers, holly, and bushes in the winter & autumn.Source: https://www.diva-portal.org/smash/get/diva2:197053/FULLTEXT01.pdf
However, this study concludes whether deer invariably like eating grass because we don’t know whether the deer have any other choices to compare or just the grass to feed on. IMO, they’ll choose a better substitute if it’s available because they are Concentrated selectors.
Another research is done in Uttarakhand, India clearly shows that Swamp Deer (Barahshinga) are mixed feeders that mostly feed on Graminoids (grasses & sedges) and Herbs (terrestrial & aquatic). It is seen that Swamp deer commonly concentrate on grasses during high rainfall (& a high rate of grass growth). That is slowly replaced by terrestrial and aquatic grass in winter & summer.
Another study shows that Roe deer (Capreolus capreolus) is a relatively small ruminant and, with its viscous saliva and unstratified rumen content, is generally classified as a strict browser along the browser-grazer continuum. However, its diet frequently contains ≥ 25% grass.
Video proof shows deer eat grass
So much reading, research published in text form. Here is some video proof that clearly shows deer eat grass.
Video Proof 1
Video Proof 2
Video Proof 3 (Sambar Deer)
Video Proof 4 (Swamp Deer)
Conclusion: What Our Finding Says?
After all our research, I can say that deer do eat grass but not often because they have Prehnsile lips & narrow muzzles that help them choose highly nutritious food. So, we found that deer chooses grass only when there’s no better substitute near them when they are most hungry.
As they’ve small rumen, they don’t need much nutrition for maintenance, so if they have a half-filled stomach and grass is nearby them, IMO, they will try to find other forages or more highly nutritional grasses because there are over 12,000 species of grass around the world.
It is also hard to say which species of deer like the grass most as there are at least 43 known species of deer around the world. Though, our findings show, Swamp deer like the grass more as in summer over 60% of their diet contained grasses.